Present mining methods involve the use of a combination of apparatuses to drill holes in rock, place explosives in the hole and then initiate the explosives to fracture the rock.
A typical drilling apparatus for such purposes is controlled by a motor which applies rotation torque to the drilling head of the apparatus and a mechanism to apply a forward force to the drilling head. The means for applying torque and force may be one or a combination of hydraulic motor or cylinder, pneumatic motor or cylinder, or electric motor. Various mechanisms are used to couple the source of torque or force to the drilling head including use of chains, rope or gears or leavers.
In any drilling operation it is desirable to maximise the rate of penetration of rock which is drilled while maintaining hole accuracy. However this is a difficult objective and to date has not been successfully achieved. Thus although for a given type of rock or material which is being drilled, there is an optimum feed force for a given rotation torque, no apparatus has been developed which successfully controls the drill to ensure a continuous maximum penetration rate of rock throughout the length of hole.
The present invention provides a method and system for controlling a drilling apparatus to enhance penetration rates during drilling operations.
It should be understood that drilling apparatuses are intended to cover different types of cutting apparatuses for excavating material such as rock in mining or other applications such as percussive and rotary drills.